Electric clock-train



N0. 610,229. Patented Sept. 6, I898. C. M. CROOK.

ELECTRIC CLOCK TRAIN.

(Application filed Apr. 29, 1897 (No Model.) 2 Sheets-Sheet I.

Patented Sept. 6, I898.

C. M. CRUOK.

ELECTRIC CLOCK TRAIN.

(Application filed Apr. 29 1897.)

2 Sheets-$heet 2.

(No Model.)

1m: nomm PETERS co, womunm" w/vfummow n. cy

UNITED STATES PATENT OFFICE.

CHARLES M. CROOK, OF ELGIN, ILLINOIS, ASSIGNOR TO CHARLES S. BURTON,TRUSTEE, OF OAK PARK, ILLINOIS.

ELECTRIC CLOCK-TRAIN.

SPECIFICATION forming part of Letters Patent No. 610,229, datedSeptember 6, 1898.

Application filed April 29,1897. Serial No. 634,313. (No model.)

T (11 whom it may concern.-

Be it known that 1, CHARLES M. CROOK, a citizen of the United States,residing at Elgin, in the county of Kane and State of Illinois,

have invented certain new and useful Improvements in SynchronizingClock-Movements, which are fully set forth in the followingspecification, reference being bad to the accompanying drawings, forminga part IO thereof.

In the drawings, Figure 1 is a side elevation of a clock-movementembodying my invention. Fig. 2 is a section at the line 2 2 of Fig. 1.Fig. 3 is a detail forward side eleva- I 5 tion ofa portion of the trainupon which the synchronizing-lever acts. Fig. at is a front elevation ofthe movement. Fig. 5 is a detail section at the line 5 5 on Fig. 4. Fig.6 is a detailsection at the line 6 b on Fig. 4. Fig.

7 is a detail section.

A distinguishing feature of my invention is that the train from themotor-shaft to the seconds hand, including the train which drives thehour and minute hands, may be positive-that is, without slip-joint orfrictional connection such as is usually provided to permit setting thehands-and that the escape-wheel or other governing device is notactuated positively in such train, but in a branch or offshoot trainfrom the hands-train, which has a frictional or slip connection with thelatter. Most conveniently and therefore preferably the branch trainleading to the escape-wheel is as a whole frictionally driven W 3 5 fromthe principal hands-train; but it will be obvious upon consideration ofthe structure that frictional or slip connection at any point in suchbranch train anterior to the escapewhcel would yield substantially thesame result. This feature of my invention is illustrated associated witha specific synchronizing-lever action, which is the subject of anapplication filed by me in the United States Patent Oflice on the 11thday of January,

1897, Serial No. (3l8,805, and the specific features of said action areherein illustrated only for the purpose of completely exhibiting anentire operative structure and will not be claimed herein.

Other detail features of my improvements in the movement are set forthin the claims.

A a are respectively the front and rear plates of a clock-movement.

B is the main shaft, actuated in any way. As illustrated, B is thespring-housing, and B a pawl-and-ratchet structure by means of which thespring when properly coiled reacts to rotate the shaft B.

My invention is not concerned with the spe cific means of communicatingmotion to the principal shaft, and therefore these features are onlyillustrated conventionally and without detail. The shaft B extendsthrough the front plate and constitutes the staff of the minute-hand D.

C is a pinion thereon which meshes with the gear-wheel C, which mesheswith and drives gear C, whose shaft is the sleeve C journaled outsidethe minute-hand staff and carrying the hour-hand E. On the shaft 13 andrigid therewith there is also a gear-wheel F, which meshes with thepinion F on the shaft f", which has rigidwith it at the forward end agear-wheel F which meshes with pinion F, whose shaft f is journaled onthe front plate A and extends therethrongh and constitutes the shaft ofthe seconds-hand G. On the shaft f is a gearwheel H, which isfrictionallyheld and driven between two frictiondisks H, which is formedas a flange on the pinion F and H, which is .mounted on the shaft at theopposite side of the gear Hfroni the disk H and is pressed against saidgear by the spring-tripod H which in turn is stopped by the collar Hwhich is rigid with the shaft f. The gear H meshes with apinion J on theshaft j, rigid with which is the escape-wheel K. The shaft j obtainsbearing at the rear end in the plate a. At the forward end it is reducedin diameter and extends into the hollow shaft f of the pinion F andthereby in addition to obtaining bearing supported on the plate A itafiords a steadying-bearing for said hollow shaft f The gears F and IIare equal in size and in the number of their teeth, and the pinions F"and J are also equal, so that the two shaftsj and f move together and sowithout friction one upon the other in the ordinary running of theclock, but are capable of entirely independent movement.

It will be seen upon consideration of this structure that the train fromthe motor-shaft B of the hands is positive and that any setting movementwherever initiated in the train will set all the hands and communicatemovement back to the motor-shaft, so that the hands being rigidly setandsecured on their respective shafts in position to harmonize in theirindications on the dial will continue so related through all settings,and that in such setting or synchronizing action the escape-wheel orother governing-wheel is not actuated and does not interfere with thesynchronizing action, because such governingwheel is driven onlyfrictionally by the train which is actuated to synchronize. It maybeunderstood that this feature of myii1vention making the connectionbetween the governing-wheel and motor-train frictional and notpositive-is practicable only when the action is such that themotor-shaft is driven with comparatively light force, so light that itis inadequate to slip the frictional connection with the escape-wheel orother governing device; and I design this invention to be usedprimarily, and perhaps it may be found useful only, in connection withself-winding clocks in which the rewinding by electrical impulse orotherwise occurs so frequently as to require only a light spring orother form of storage-motor. It will be understood from the nature ofthe result aimed at in this part of my invention that in describing theconnection of the principal or hand-actuating train with the motor-shaftas positive it is not necessary to require (since it is not necessary toprovide) that the connection should be absolutely unyielding, but onlythat it should be sufficiently so to insure transmission of the movementboth waysthat is, from the motor-shaft to the hands in the ordinaryrunning of the clock and from the hand-shafts or an intermediate pointback to the motor-shaft in the setting movementand that such connection,styled positive, should be less yieldingthat is, more nearlypositive-than the connection between the governing-wheel and themotortrain, which is termed frictional that is to say, the termspositive and frictional as applied to these two connections arerelative, the connection called frictional being com parativel y easilyyielding and the connection called positive not being so easilyyielding--and the description in these respects is not to be construedas inconsistent with or excluding a structure adapted to permit the hourand minute hands to be set by hand at any point in the dial regardlessof the train. In connecti )n with this movement I have employed asynchronizing or setting mechanism which, except as to certain details,is similar to myapplication, SerialNo. 618,805, above mentioned, andwhich will now be described sufficiently for the purpose of pointing outin detail certain improvements relating thereto.

L is an electromagnet in circuit with a controlling-clock, the circuitbeing closed at the time for synchronizing or setting all the clockswhich are so connected, and such setting being effected by the movementsof the armature L when it is attracted to the magnetpoles upon theenergizing of the circuit of the latter. The armature L is mounted onand rigid with the rock-shaft L journaled in the front and rear plates Aand a and having a lever-arm U, which extends across behind the wheel Fof the train. The rear bearing of the rock-shaft L in plate a iselongated obliquely, as seen in Fig. 4, so that in addition to theordinary rocking movement of the shaft in its bearings it has capacityfor an oscillating movement at the rear end, the direction ofoscillation being determined by the direction of elongation of the rearbearing, such elongation'having the effect of swinging the leverarm Ltoward and away from the gear F while it oscillates also up and downpast or adjacent to said plate on account of the rocking movement of therock-shaft. From this structure it results that when the armature isfree from the attraction of the magnet the rock-shaft drops to the lowerouter limit of the rear bearing and the arm L stands in the positionshown in dotted lines in Fig. 2, its free end being more remote from thewheel F than the end at the rockshaft, and when the armature isattracted to the magnet the rear end rising also moves inward, followingthe elongated bearing, and the arm L swings forward toward the heel Fwhile it moves downward. The lever-arm L has two abutments or studs L Lprojecting forward. When the arm is in the position shown in dottedlines in Fig. 2, these studs are wholly at the rear of the plane of thewheel F; but when the lever-arm is thrown downward and forward and whenthe armature is actuated toward the magnet these studs or abutmentspenetrate the plane of the wheel F and as the lever-arm descends areadapted to collide with the spokes of the Wheel at opposite sides of thevertical plane through the axis, and so colliding they force the Wheelto a definite position, rotatin git one way or the other, accordin g tothe variance of the positions of the two spokes before collision fromthe position to which the movement of the lever with its studs collidingwith and acting upon the spokes will bring the latter-that is, if, forexample, the wheel is too far advanced the spoke at the right-hand sideor nearest the rock-shaft will be struck by the stud L and the wheelwill be actuated to set back the hands, this movement being arrested,however, and ending when as a result of it the other stud L meets theopposite spoke of the wheel. If the clock is slow and requires to be setforward, the stud L will be the first to collide with the spoke on thatside, and the movement thus caused will be arrested by the collision ofthe other stud with the opposite spoke.

In respect to the synchronizing features as 5 f to a point directlyabove the shaft B, andthus far described the structure is identical withthat illustrated in my abo\- e-mentione .l application, Serial No.618,805.

lVhen clocks of a system designed to be synchronized together are usedtogether in such situation as to permit the employment of atelegraph-line to be used as the connecting-circuit-for example, in caseof clocks located at several stations of a railroad-it is desirable toavoid the necessity of constructing an independent circuit, and for thispurpose it is customary to connect the clocks by proper switches withthe telegraph-line for a very short time about the hour ofsynchronizing, the line being for that time held out of other use. \Vhenthis method prevails, if after the synchronizing action has occurred theoperator at any station neglects to disconnect the clock an impulse Willbe experienced by the armature at every opening and closing of atelegraph-key in the ordinary use of the line in sending messages, andin the absence of any device to prevent such result the clock would inthat event be reset at every such impulse back to twelve oclock, thatbeing the synchronizing hour. This would evidently defeat thesynchronizing action which was performed at the proper time, because itwould set the clock slow by as many minutes as had elapsed after twelveoclocl: before such resetting occurred. To avoid such a result, Iprovide the lever-arm If with a branch If, which extends down in adirection to avoid interference with the shaft on said shaft there issecured a drum M, having a flange M. A stud t", projecting from thebranch If of the lever L overhangs the periphery of the drum restingthereon when the armature is free from the influence of the magnet, andat a corresponding position of the lever If the latter is stopped in theopposite direction by the finger N, which projects from the frame-plateA. The flange M of the drum is designed to stop the lateral movement ofthe branch I when the lever is swung laterally toward the plane of thewheel F The drum M has a slot or channel N extending from its peripherythrough the body or across the face, such slot or channel being widerthan the diameter of the pin 1* by an amount corresponding to themaximum allowance for syn chronizing-that is to say, the slot having itsopening at the periphery of the drum in a position to coincide with thepin at the synchronizing hour, say twelve ocloclr. Said slot is widerthan the diameter of the pin an amount sufficient to permit it.

to be under the pin, so that the latter can enter it for a length oftime before and after the synchronizing hour equal to the maximum errorwhich the synchronizing action is calculated to correct. The maximumcorrection, it will be understood, is the maximum movement which thehands can receive from the collision of the studs L and L with thespokes of the wheel F and in practice it is not necessary that the clockbe adapted for a maximum correction of more than one minute each way.

The telegraph-line used for the synchronizing-circuit would be held outof other use for a period somewhat longer than the maximum correction,and during that time the drum M would rotate far enough to carry themouth of its slot away from the stud Z", so that if after that periodthrough failure to switch the clock out of the circuitthe magnet shouldreceive an impulse the armature could not respond to the attraction ofthe magnet, as it would be locked out of position by the 106 gment ofthe stud Z on the periphery of the drum M. It will be understood thatthe slot N extends across the face of the drum in a course which wouldbe in the arc of a circle about the axis of,the rock-shaft L when thedrum occupies the position such that the stud l can enter the slot.

I claim- 1. In a clock-movement,in combination with a motor such as ainainspring,a principal train actuated thereby in the ordinary runningof the clock,extending to and including the staffs of all thetime-indicating hands and a governing device, the latter being actuatedsolely by frictional connection with the anterior portion of the train,and all the hand-staffs being actuated in such anterior portion, suchfrictional connection of the governing device being adapted to endurewithout slipping the full driving power transmitted to it by the train.

2. In a clock-movemen t,in combination with a motor such as a mainspring,a principal train actuated thereby in the ordinary running ofthe clock, extendin g to and including the staffs of the minute and hourhands and a governing device, the latter being actuated solely byfrictional connection with the anterior portion of the train, and allthe hand-stafis being actuated in such anterior portion, such frictionalconnection of the governing device being adapted to endure withoutslipping the full power transmitted thereto by the train.-

3. In a clock-movement,in combination with a motor such as a m ainspring; a principal train actuated thereby in the ordinary running of theclock and extending to and including the seconds-hand, and a governingdevice; a secondary or offshoot train actuated solely by frictionalconnection with a principal train and leading to and including agoverning device, such frictional connection of the offshoot train beingadapted to endure without slipping the full driving power transmittedthereto by the train.

4. In a clock-m vcment,in combination with a motor such as a mainspring,a principal train actuated thereby extending to and including the staffsof all the time-indicating hands, and a governing device, the latterbeing actuated solely by frictional connection with the anterior portionof the train, and all the hand-staffs being actuated and positivelycon-- IIO nected in such anterior portion, such frictional connection ofthe governing device being adapted to endure without slipping the fulldriving power transmitted thereto by the train, a synchronizing deviceadapted to act upon one ofthe positively-connected wheels of suchhands-train, and suitable extraneous means foroperating thesynchronizing device.

5. Inaclock-movement,in combination with a motorsuch as a mainspring, aprincipal train actuated thereby, such train extending to and includingthe staffs of the minute and hour hands, and an escape-wheel, the latterbeing actuated solely by frictional connection with the anterior portionof the train, and the minute and hour hands being actuated andpositively connected in such anterior portion, a synchronizing device toact upon one of the positively-connected hand-actuating wheels, andmeans for actuating such synchronizing device.

6. In a clock-movement, .in a combination with a motorsuch as amainspring, theprincipal train actuated thereby extending to andincluding the seconds-hand, a secondary or offshoot train actuated byfrictional connection with the principal train, such offshoot leading toand comprising an escapewvheel; a synchronizing device adapted to actupon a wheel in the principal train positively connected with theseconds-hand staff, and means for operating the synchronizing device.

'7. I11 combination with the hands-trainof a clock, an electromagnet onthe frames, a circuit in which it is energized, an armature for suchmagnet, a lever connected thereto and actuated thereby and adapted toact upon a wheel in said train when the magnet is energized, a disk onsaid lever having a projection adapted to encounter a Wheel on the shaftof the train when the armature experiences the initial impulse of themagnet, said wheel having a path for the projection at a position on thewheel which coincides with the path of the projection in its movementwith the lever at the synchronizing hour, the amplitude of said path inthe wheel being in excess of the actual path of the projection by anamount corresponding to the maximum correction for which thesynchronizing device is calculated.

In witness whereof I have hereunto set my hand, at Chicago; Illinois,this 24th day of April, 1897 in the presence of two witnesses.

CHARLES M. OROOK.

Vitnesses: 7

CHAS. S. BURTON, JEAN ELLIOTT.

